Stone polishing machine



Patented Nov. 25, 1952 Charles S. Cushman, BarreLVt., vassgnor to Charles S. Cushman, Paul G. Cushman, and Victor v'ilan-borini, vcopartners, doing business under Jthe name of The Cushman Company,

Barre, Vt.

ApplicationFebruary 9, 1949, Seri'al No. 75,343

8 Claims. (Cl. '5l-126) This invention relates to improvements instone polishing :machines and particularly the type of machine disclosed in my prior lPatent No. 2,055,404 issued September 22, :1936. l K

It is old and wellk-now-n inthe art toA make polishing machines 'with a longitudinal mov-able supporting beam, one end of the beam carrying thev grinding or 1iinish-ing wheel and a .driving motor for the wheel .mounted on the other end. y'I'he supporting beam lis suspended. .from a pivotaily mounted trolley and has mechanism for longitudinally Ysluit-ing the beam with respect to the trolley to unbalance the ends `of the beam to adjust the pressure of .the -grind-ing wheel onvthe bed `of stone being polished. .In machines of this character the operator manually swings the suppor-.ting beam in a lateral vor .sidewise direction to move the grinding wheel over the area of the stone toA be polished. As the size of the grinding wheel increases the manual shifting of the supporting beam becomes .more dinicu'lt due to the increase `in the weight of the beam. At the present time the size of the grinding wheel is limited by the physical ability. of the operator to manually shift thefsupp'or'ting beam.

yIt .is the. .primary object of the present'invention to provide power mechanism for shifting the grinding wheel supporting beam laterally of the bed of stone being polished without any manual work on the v.part of the operator thus permitting the 'usev ofgrind'ing stones of very large sizes.

A Vfurther object of the invention resides in providing a movable crane mounted .for longitudinal movement ofthe supporting beam for Vthe grinding wheelcarrying power mechanism 'for laterally swinging the, supporting beam in a horizontal plane. v

A still 'further object of the invention resides in providing a movable crane having power mechanism for laterally shifting 'the supporting beam lof the .grinding wheel and a movable power hoist carried 'by the crane for raising vand lowering the supporting beam and grinding wheel.

Another object of the invention resides in providing mechanism Aof the ycharacter described which 's simple and durable in construction, re'- llable vand efficient in operation and inexpensive to manufacture. A

Other objects and advantages of the invention will be apparent during the course of the followingV description.

In theA accompanying drawing forming a part of` this 'specification and in which like numerals are employed to designate .like parte throughout the same,

Fig. l is -a front elevational view of the improved mechanism., d I A Y Eig.. .2 is a detail top plan view of the power means for the shifting mechanism, A

Fig. I3 is a detail .iront elevational View of the supporting beam for the grinding wheel yshowing the connections between the shifting mechanism and supporting beam, and,

Fig. 4 is a top plan view ci the detail shown in 3. o

Referring to the drawings wherein .for the purpose of illustration a preferred embodiment of the invention is shown, the numeral '5 denotes the supporting beam for the grinding wheel. '6 which is attached to -a vertical shaft l .journaled in one end of the beam. The driving means for the shaft 'I is similar to the driving means shown in my prior Patent 2,055,404, and as disclosed in my prior patent mechanism yfor moving the supporting beam longitudinally with respect Ito its support is "provided 't'o unbal'ance the beam and adjust the 'pressure of the .grinding wheel on the bed 'of 'stone bein'g polished. Polishing machines of 'this class are old and well known `inthe art and the present 'invention relates to improvements 'for use with machines of this 'general type when made in. large sizes.

The improvement comprisesfa traveling crane generally designated at 8 which is' uesh'ape with a horizontal member 9 `formed of spaced channel irons and vertical 'side members I0 formed 'of spaced angle irons. rIhe horizontalmember Q at each end is suspend-ed by trolley wheels 'II which ride on the lower ii'anges of I beams I2 attached to a xed frame I3. .The `I beams I2 extend longitudinally of the polishing machine and have their rear ends lsupported by .a frame similar to the frame I3. `The crane '8 by reason of the trolley'wheels is movable longitudinally of the beams I2 withuthe side members I) disposed on opposite sides of the supporting beam 5 of the polishing machine. y y

Mounted intermediate the ends of the horizontal member `9 and between the channel meinbers thereof is a drum I4 mounted 'on a 'shaft I5 journaled in bearings I`6 attached to the channel members. An auxiliary frame I1 isattached to member 9 and surroundsv the drum III. An electric reversible motor I8 is mounted on the frame and by means of a belt I9 drives the reduction gearing in housing 20 connected with the shaft I5 through driven gears -2I and 22. A cable is wound on the drum I4 with its ends 23 and 2s extending in opposite directions, so that when one of the ends is being wound kon the drum the other end is unwinding. The ends of the cable are trained over sheaves 25 mounted at each end of member 9 and then pass down between the angle irons of side members I around the adjustable sheaves 2B at the lower ends of the side members. The adjustable sheaves 25 are held in the slots formed by the spaced angle irons by bolts 2'I and are movable vertically of the side members to adjust their position with respect to the beam 5 of the polishing machine. The end 23 of the cable is attached to a bolt 28 slidably mounted in an angle bracket 29 mounted on beam 5. A coil spring 30 is mounted on bolt 28 between the bracket 29 and nut 3| on the end of the bolt to provide a yieldable connection between the cable and beam which absorbs the shock when the cable pulls on the beam. The end 24 of the cable is attached to a take-up drum 32 mounted in arms 33, 34 attached to the beam 5 opposite the bracket 29. A ratchet wheel 35 is attached to one end of drum 32 which is engaged by a pawl 36 pivotally mounted on arm 34. A crank 31 attached to the shaft of drum 32 provides manual means for turning the drum to wind the cable thereon to take up the slack in the cable and tighten the same. Y

As shown in Fig. 1 a movable carrier 38 is suspended from the member 9 by trolley wheels 39 which ride on the anges of the channel irons. The carrier 38 is freely movable longitudinally of the member 9 and supports a conventional motor operated chain hoist 4U having its grab hook 4I connected to a ange plate 42 attached to the beam 5 of the polishing machine. The hoist operates to raise and lower the beam 5 and grinding wheel 6. A

In operation, when the beam 5 is moved longitudinally relative to its supporting trolley, the pressure of the polishing wheel on the bed of stone to be polished is adjusted. As the beam 5 moves forward or backward relative to its support the crane 8 will also move forward or backward along its supporting beams I2. The motor I 8 and motor of the chain hoist 40 are controlled by switches interposed in the circuits of the motors. When it is desired to shift the beam 5 laterally of the bed of stone the operator closes the switch controlling the motor I8 which rotates drum I4 to Wind and unwind the ends 23 and 24 of the cable wound thereon. The motor I8 is reversible to rotate the drum in either direction and when the drum is rotated it pulls on either the end 23 to swing the beam 5 to the left or the end 214 to swing the beam to the right. The shock of the pull on the beam is absorbed by the spring 30 of the yieldable connection between the end 23 and the beam. Any slack in the cable between the drum I4 and beam may be taken up by winding the end 24 on the take-up drum 32. As the beam 5 swings to the right or left the chain hoist 40 attached to the beam by grab hook 4I moves with the beam as the carrier 38 is freely movable on the horizontal beam 9 of the crane 8. When it is desired to raise or lower the beam 5 the motor of the chain hoist is operated. Thus it is seen I have provided power mechanism for laterally shifting and raising and lowering the supporting beam which carries the grinding or iinishing wheels, permitting the use of much larger grinding wheels.

It is to be understood that the form of my invention herein shown and described is a preferred example of the same and changes in the shape, size and arrangement of the parts may be made Without departing from the spirit of the invention or scope of the subjoined claims.

Having thus described my invention, I claim:

1. A stone polishing machine comprising a longitudinal movable and swinging beam, a polishing whee1 mounted on one end of said beam, a traveling crane mounted above said beam for free longitudinal movement thereof including a horizontal member having depending side arms on opposite sides of said beam, guide sheaves mounted in the horizontal member and side arms of said crane, a flexible cable trained around said sheaves having its ends connected to opposite sides of said beam, power means carried by said crane operably connected to said cable for pulling said cable in opposite directions to swing said beam in a horizontal plane, and a power hoist movably mounted on the horizontal member of said crane and connected to said beam for raising and lowering the same.

2. A machine of the character described in claim 1 including a yieldable connection between one end of said cable and said beam.

3. A machine of the character described in claim 1 including a take-up drum carried by said beam to which one end of said cable is attached.

4. A stone polishing machine comprising a lon` gitudinal movable and swinging beam, a polishing Wheel mounted on one end of said beam, a frame straddling said beam, spaced longitudinal rails carried by said frame, an inverted U-shaped frame suspended from said rails and movable longitudinally thereof, the side arms of said U- shaped frame being disposed on opposite sidesv of said beam, a flexible cable having its ends confnected to opposite sides of said beam, guide sheaves mounted in said U-shaped frame around which said iiexible cable is trained, and power means operably connected to said flexible cable for pulling said flexible cable in opposite directions to swing said beam in a horizontal plane.

5. A stone polishing machine comprising a 10ngitudinally movable and swingably mounted beam, a polishing wheel mounted on a spindle journaled in bearings on one end of said beam, a crane including a horizontal member having rigid depending side members at each end rigidly connected to said horizontal member, means suspending said crane above said beam for free longitudinal movement thereof with the side members disposed on opposite sides of the beam in spaced relation thereto, draft means connected to opposite sides of said beam adjacent the end supporting said polishing wheel and extending to the side members of said crane, and power means connected to said draft means to swing said beam in a horizontal plane in opposite directions.

6. A machine of the character described in claim 5 including a power hoist mounted for longitudinal movement on the horizontal member of said crane and connected to said beam for raising and lowering the same.

'7. A stone polishing machine comprising a longitudinally movable and swingably mounted beam, a polishing wheel mounted on a spindle journaled in bearings on one end of said beam, a crane including a horizontal member having rigid depending side members at each end rigidly connected to said horizontal member, means suspending said crane above said beam for free longitudinal movement thereof with said side members disposed on opposite sides of said beam in spaced'relation thereo, a flexible cable having its ends connected to oppostie sides of said beam REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 8,150 Eames June 10, 1851 194,233 Field Aug. 14, 1877 481,988 Weyburn Sept. 6, 1892 .Number Number 6 Name Date Lavers Aug. 7, 1894 Browning Apr. 12, 1904 Yarnell Sept. 8, 1908 Maher` June 6, 1911 Shoemaker' May 18, 1915 Spears Jan. 9, 1917 Breidenbach Nov. 13, 1928 Owen June 4, 1929 Crane Jan. 13, 1931 Hanna Sept. 6, 1932 Clark Nov. 6, 1934 Cushman Sept. 22, 1936 Cumming Mar. 9, 1937 Cumming June 9, 1942 FOREIGN PATENTS Country Date Germany July 28, 1922 France Aug. 1, 1930 

